Deep water pumping of fluids and semi-fluids

ABSTRACT

A ROTARY PERSISTALIC PUMP FOR PUMPING FLUIDS AND SEMIFLUIDS IN UNDERWATER LOCATIONS INCLUDES A SEMI-CIRCULAR PIECE OF COMPRESSIBLE TUBING DISPOSED AROUND THE INNER ARCUATE SURFACE OF A SUBSTANTIALLY WATER-TIGHT HOUSING WITH PUMP ACTION OBTAINED BY A PAIR OF POWER DRIVEN COMPRESSION WHEELS. A CHECK VALVE MOUNTED ON THE HOUSING AND COMMUNICATING WITH THE INTERIOR THEREOF IS USED TO MAINTAIN A PREDETERMINED PRESSURE DIFFERENTIAL BETWEEN THE INTERIOR AND EXTERIOR OF THE HOUSING.

ATTORNEYS J. T. BROADFOOT DEEP WATER PUMPING OF FLUIDS AND SEMI-FLUIDS Filed March 18, 1970 June 13, 1972 6 v m l 2 2 .m 5 lull. I hm /VV VMMV VMV Mhh Km United States Patent 3,669,574 DEEP WATER PUMPING 0F FLUIDS AND SEMI-FLUIDS John T. Broadfoot, 12714 Aurora Ave. N., Seattle, Wash. 98155 Filed Mar. 18, 1970, Ser. No. 20,501 Int. Cl. F04b 43/08, 43/12, 45 06' US. Cl. 417-477 3 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Field of the invention This invention relates to a rotary peristaltic pump designed for deep water pumping of mud and other sermfluids.

PRIOR ART RELATING TO THE DISCLOSURE Rotary pumps of the type which employ a loop of compressible tubing disposed around the inner surface of the housing with pumping action obtained by compressing the tubing in regular cycles are known. Pumps of this type have been used to pump fluid and semi-fluids of various kinds. As far as is known, pumps of this type have not been used in pumping fluids and semi-fluids in deep underwater locations where the exterior pressure exerted on the pump is relatively high. Efliciency of pumping action in pumps of this type is dependent on the elasticity or memory of the compressible tubing and on the pressure difierential between the interior and exterior of the housing. The pressure differential in addition to the elasticity of the tubing enables the tubing, once compressed, to return to its original configuration almost immediately. When operating in deep water, for example, at a depth of 1200 to 1500 feet, the external pressure exerted by the Water on the pump is considerable. To work efliciently the pump must have an internal pressure less than that of the external pressure. If the pressure differential becomes too great, however, serious problems in the integrity of the compressible tubing result.

SUMMARY OF THE INVENTION This invention relates to a submergible rotary peristaltic pump for pumping fluids and semi-fluids in underwater locations. The pump may be used in assisting re covery of sunken objects from the bottom of bodies of water, such as the ocean floor, where the objects are many times buried in mud. To retrieve such objects it is necessary to remove a certain amount of the mud and muck surrounding the object. This is usually accomplished by pumping the mud surrounding the object to a different location. Conventional pumps such as centrifugal pumps are easily clogged by occasional objects in the mud and debris found on the sea floor. A great deal of expense and time are necessary to unclog them. The pump of this invention is able to pump fluid and semi-fluids containing occasional solids having a diameter as great as that of the compressible tubing without difficulty. This 3,669,574 Patented June 13, 1972 pump is also capable of operating efiiciently at any desired depth.

The pump of this invention has a self-regulating feature which maintains the pressure differential between the interior and exterior of the pump housing substantially constant even though the depth of the pump is changed with a corresponding change in the external pressure exerted on the pump.

The pump comprises a substantially water tight housing having inlet and outlet ports cut therethrough, a continuous compressible tube extending through the inlet and outlet ports and disposed around the interior wall of the housing, and compression means mounted in the housing for rotation around the inner surface of the housing for progressively compressing the tube to closure against the interior wall thereof. The pressure differential be tween the interior and exterior of the pump is maintained substantially constant by a check valve interconnecting the interior and exterior of the housing. A hydraulic motor or other suitable means is used to drive the compression means compressing the compressible tube. A suction pump integrally mounted on the peristaltic pump and driven by the hydraulic motor connects with the interior of the pump housing and is used to assist in main- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of the pump of this invention;

FIG. 2 is a plan view of the pump shown in FIG. 1;

FIG. 3 is a sectional view along section line 3-3 of FIG. 2 showing the interior of the pump and the location of the compressible tube.

DETAILED DESCRIPTION OF THE INVENTION The pump of this invention comprises pump housing 10 within which is mounted compressible tube 20 and compression means 30 for compression successive contiguous areas of the tube to closure against the interior walls of the pump. Power means 40 moves the compressing means around the interior walls of the housing. Water or other fluid is admitted to the interior of the pump housing under regulated conditions through valve 44. Power means 40 also drives suction pump 42 which connects to the interior pump housing 10.

In more detail pump housing 10 comprises two parallel spaced apart sidewalls 11 and '12 between which are placed end wall 13 and bottom wall 14. The configuration of the pump housing is typically cylindrical. At the lower end of the housing are located inlet and outlet ports 15 and 16 respectively. The pump housing is made substantially water tight by conventional means. Around the arcuate inner surface of the pump housing is placed a liner 17 of resilient material such as rubber, the function of which is to prevent damage to the compressible tube by cushioning it against coarse or sharp objects which may be present in the pumped material.

A loop of compressible tube 20 of uniform cross section is placed around the inner arcuate surface of the pump housing 10. One end of the compressible tube 20 is connected to suction pipe 21 extending through port 15 of the pump housing and the other end of the compressible tube is connected to discharge pipe 22 extending through outlet port 16 of the pump housing.

of parallel plates 30 held apart by reinforcing'members 31 and rigidly attached in axially-spaced relation to the drive shaft 32 which extends'through the end walls of the housing. Diametrically opposed compression wheels 33 are journaled for rotation on shafts 34 carried by plates 30. The compression wheels 33 are mounted in the same plane such that on rotation of the plate 30 theyprogressive'ly compress successive contiguous areas of the compressible tube to closure against liner 17 and the'inner surface of the end wall 13 of pump housing 10. The compression wheels 33 are suitably pneumatic tires mounted on hubs. The compressible tube 20 is maintained in alignment with compression rollers 33 by guide rollers 35, 36, 37 and 38. The guide rollers are of smaller diameter than the compression wheels and are journaled for rotation on shafts 39 carried by pump plates 30. Guide rollers 35 and 38 are diametrically opposed to one another and are mounted so as to contact opposite sides of the compressible tube. Likewise, guide rollers 36 and 37 are mounted so as to contact opposite sides of the tube.

Plates 30 and compression wheels 33 thereon are rotated by means of hydraulic motors 40 connected to the shaft 32 on each side. Other means of powering the pump rotor can be used if desired. 1 Connected to one of the motors of the pump rotor is suction pump 42 of conventional design which has its intake end in communication with the interior of the housbecomes greater than desired. Usually the valve is adjusted to open when the pressure differential between the interior and exterior of the housing is from 15 to 30 p.s.i.

Also connected to and communicating with the interior of pump housing 10 is pipe 46 which extends upwardly from the lower end of the pump housing a short distance.

The end of the pipe is capped. Air is trapped in the pipe 46 and functions to even out pressure fluctuation which occur as the pump rotor rotates about its axis. The expansion chamber created by pipe 46 evens out the pressure fluctuations which, otherwise, cause an unstable condition in the pump.

Outlet pipe 22 extending through outlet port 16 is connected to discharge hose 48 which carries the pumped material to the desired discharge location.

If the suction pipe 21 of the pump should become clogged provision is made for unclogging the pump if the material clogging the pipe is mud or other material which will dissolve readily on contact with water. An L-shaped pipe 50 attached to the lower end of suction pipe 21- extends upwardly a short distance. On the upper end of pipe 50 is a dilution valve 51, opening and closing of which is remotely controlled by suitable mechanical or electrical means. When suction pipe 21 becomes clogged dilution valve 51 is opened allowing water to enter pipe 50 and v I suction pipe 21 where it dissolves the mud or other material clogging the pipe.

In operation the pump of this invention is lowered to the bottom of theocean floor or river as the casemay be by a cable 52 attached to the housing. Running along the cable 52 are hydraulic lines (not shown) leading to hy-' draulic motors 40. Valve 44 is adjusted to open at a pressure dilferential between the interior and exterior of the pump housing of approximately 15 p.s.i. As.the pump is lowered the pressure exerted on the exterior. of the pump becomes greater than that on the interior. When the pressure differential exceeds 15 p.s.i. valve 44 opens allowing water to flood the interior of the pump housing. When the pump reaches the operatingdepth the hydraulic motors'are started by remote control. Revolution of the hydraulic motors rotates plates 30 and compression wheels 33. The hydraulic motors also turn suction pump 42 which assists in maintaining the pressure; diiferentialbetween the interior and exterior" of the pump, at 'the preset 'pressure differential. Mud and other debris are sucked into suction pipe 21 and is discharged throught-hedisch'argeliose 48.

The advantage the pump of this invention offers over other known pumps for deep sea. operations is that it is capable of pumping semi-fluids having occasional solids of a diameter as great as that of the compressible tubing without damage to the pump and without any substantial clogging thereof. Additionally, the pressure differential maintained between the interior and exterior .of the pump housing by the combination of suction pump and valve enables the pump to: be used at various 'dep thswithout modification or change of any kind. H

In summary, the pump of this invention constitutes an efiicient and, easy to maintain pump for use. in assisting in the recovery of objects from the ocean floor from'the bottoms of rivers, and other inaccessible underwater locations.

The embodiments of the invention in which an exclusive property or privilege'is claimed are'defined as follows:

1. A submergible, self-regulating rotary peristaltic pump for pumping fluids and semi-fluidsat varyingdepths in underwater locations while maintaining a substantially constant pressure differential between the interior and exterior of the pump with changes in operating depth, enabling the pump to work efficiently, comprising: i

a water-tight housing initially filled with air, having an interior wall portion, p a section of compressible tubing contained therein, inlet andoutlet ports in the housing for receiving opposite ends of the compressible tubing power driven compression .means rotating in. a path around-the interior wall of the housing with successive areas of the periphery of the compressing means compressing successive contiguous areas along "the length of the compressible tube against the interior wall of the housing during the cycle of rotation, one way pressure differential valvemeans mounted on the housing allowing water to enter the housing and increase the air pressure therein whenthe exterior water pressure exerted on the housing exceeds a preset pressure differential ,valuebetween the pressure on theinterior and the exterior of the housing, a water suction pump mountedv on the housing having its intake communicating with the interior; ofv the housing for removing water from the housing to decrease the pressure therein so as to..maintain the pressure dilferential betweenthe interior and exterior of the housing at said preset value as the ep of the pump is changed during operation, the ditferential pressure valve means andsuction pump, workingjtogether to maintain the pressure dilferential at said preset value regardless of the depth of operation of the pump and changes in the depth occurring during operation. 2. A submergible,self-regulating rotary perismnp for pumping fiuids and semi-fluids at varying depths in underwater locations while maintaining a substantially constant pressure differential between the interior and exterior of the pump with changesin operating depth, en-

abling the pump to work efficiently, comprising: I a water-tight housing ,initiallyfilled with air, having aninterior wall portion, I v

a section of compressible tubingcontained therein, inlet and outlets ports in the housing for receiving .op-

, posite ends of the compressible tubing, power driven compression means rotating infapath around the interior wall of the housing with su ccessive areas of the periphery of the compressing means 5 6 compressing successive contiguous areas along the the interior thereof for evening out pressure fluctualength of the compressible tube against the interior tions created by rotation of the compression means. wall of the housing during the cycle of rotation, 3. The pump of claim 2 including an open-ended conone way pressure diflerential valve means mounted on duit communicating With the inlet port of the pump, a the housing allowing water to enter the housing and 5 remote controlled valve covering the open end of the increase the air pressure therein when the exterior conduit, the valve, when opened, receiving water surround- Water pressure exerted on the housing exceeds a preing the pump housing in the conduit and inlet port to set pressure differential value between the pressure dilute clogged material in the inlet port of the pump. on the interior and the exterior of the housing, a water suction pump mounted on the housing having 10 References Cited its intake communicating with the interior of the UNITED STATES PATENTS housing for removing water from the housing to decrease the pressure therein so as to maintain the pres 2485208 10/1949 Longenecker 417430 sure differential between the interior and exterior of 2545,3743 3/1951 Head, 417430 X the housing at said preset value as the depth of the 15 02 8/196? Hams 417-431 pump is changed during operation, the differential 3180272 4/196 Broadfoot 417-475 X pressure valve means and suction pum working to- 3516343 5/1967 Vaughan 417-430 gether to1 maintaini1 the prgisurie dllrfierential at saidE FOREIGN PATENTS preset va ue regar ess o e ept of operation 0 the pump and changes in the depth occurring during 20 713239 8/1954 Great Bmam 47-477 and CARLTON R. CROYLE, Primary Examiner means forming an expansion tube partially filled with air mounted on the housing and communicating with R. GLUCK, Assistant Examiner 

